<!doctype html> 
<html> 
<head> 
    <meta charset="utf-8"> 
    <title></title> 
</head>
<body>
<script type="text/javascript">

(function(x,y){
	alert(x+y);
	//4  x
	//14 x
	//'1'+'3s'
	//13
})((function(){
	var a = '';
	var b = 1;
	return a+b;
})(),(function(){
	var a = '1';
	var b = 3;
	return a*b;
})());
</script>
</body>
</html>